Pressure resistant closures



Aug. 19, 1958 c. .J. JESNIG PRESSURE RESISTANT CLOSURES 4 Sheets-Sheet 1Filed Oct. 7. 1953 I Zsnventor CHARLES J. JFS/V/G Aug. 19, 1958 c. J.JESNIG PRESSURE RESISTANT CLOSURES 4 Sheets-Sheet 2 Filed Oct. 7, 195

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Aug. 19, 1958 c. .1. JESNIG PRESSURE RESISTANT CLOSURES 4 Sheets-Sheet 5Filed Oct. 7, 1953 Aug. 19, 1958 Q JES 2,848,130

PRESSURE RESISTANT CLOSURES I 4 Sheets-Sheet 4 Filed Oct. 7, 1953 R v"ms n M 7 eszzzy United States Patent PRESSURE RESISTANT CLOSURES CharlesJ. Jesnig, Newtown Square, Pa., assignor to Duo- Vent Vacuum ClosureCompany, Philadelphia, Pa., a corporation of Pennsylvania ApplicationOctober 7, 1953, Serial N 0. 384,687

3 Claims. (Cl. 215-31) This invention relates to closures, includingvacuum closures for bottles and the like.

In my earlier filed application, Serial No. 36,222, now abandoned, Idisclosed an improved bottle and sealing plug closure invention,particularly adapted for evacuation and the maintenance of the createdvacuum. This invention is not only of general interest in packaging, butalso it is especially of interest in the pharmaceutical and biologicalfields, such as for packaging serums, antibiotics, and the like. It is afeature of the invention of that recited application to combine an innerring on the neck of the bottle with a flanged rubber plug-insert groovedto engage the ring and having a flange arranged for overlying the end ofthe bottle as a sealing element. The assembly, after evacuation, waspreferably provided with a metallic retaining tear-off closure which Wasspun on the bottle and anchored thereto by an eX- ternal bead orshoulder on the neck thereof.

This present invention constitutes an improvement on the invention ofsaid application, and in the art of closures, including vacuum closuresgenerally.

It is among the objects of this invention to provide a valve and glassor like bottle assembly in which the valve can be anchored in the glassand be capable of maintaining a substantially complete vacuum; toprovide a valve insert for a ringed bottle neck having two separate andindependent sealing surfaces to enhance the seal of the valve; toimprove the art of packaging, especially in the pharmaceutical andbiological fields; to provide an improved valve element for glass andlike containers by which a hermetic seal is accomplished internally ofthe neck of an associated bottle; to provide a valve and bottlecombination in which without evacuation, if desired, a hermetic seal isestablished between the bottle and valve; to provide a valve unit andbottle by which a vacuum can be established by means of a needle passingthrough the valve unit, which latter is self-sealing to maintain avacuum when the needle has been Withdrawn; to coordinate the dimensionsof a production line of molded bottles having an internal neck ring Witha molded resilient valve unit having an anchoring groove forinterlocking engagement with such neck ring so as to anchor the valveunit against undesired retraction while holding a flange element of thevalve in sealing engagement with the end of the bottle neck; to improvethe art of molded bottles; to provide an improved closure for bottles bywhich internal pressure higher than atmospheric can be built up ordeveloped within the bottle or like container without leakage or loss ofsuch internal pressure through or about such closure; to provide animproved closure for bottles disposed for sublimation of the contents;to provide a bottle and closure plug organization in which the plugenters the neck of the bottle and effects sealing interlockingengagement with an internal neck ring on the bottle without any flangeoverlying the end of the bottle neck; to provide a bottle and plugorganization by which the expensive metal tear-oil elements previouslynecessary 2,848,130 Patented Aug. 19, 1958 in packaging certain types ofgoods is dispensed with; toprovide a plug closure for special bottlenecks which is more economical to produce than any of the prior artclosure which it replaces; to provide a closure plug for bottle necksfitting within the bottleneck and without a flange whereby many more ofthe plugs can be made in a mold in a single common heat; to provide aclosure plug comprising a shank having a peripheral groove separatingupper and lower peripherally continuous sealing surfaces forinterlocking and sealing engagement with a tapered internally projectingneck ring in a bottle neck; to provide a closure plug comprising a shankhaving a peripheral groove defining on the lower edge a generally sharpperipherally continuous shoulder for engagement under the internallyprojecting tapering neck ring to anchor the plug in the bottle neck andin which without any supplemental fastening means the plug remainsanchored despite the build up of internal pressures as may be incident,for instance, to the insertion of a physicians needle for forcing airinto the bottle to furnish pressure for Withdrawal of bottle contentsinto a hypodermic needle, with enhanced interlocking and enhancedsealing so that the pressure is retained and the interlock of the plugand the bottle is maintained and so that the plug is not forced out ofthe bottle neck by such pressure; to improve the art of packaging,especially in the pharmaceutical and biological fields; to provide animproved plug element for glass and like containers by which a hermeticseal is accomplished internally of the neck of an associated bottle; toprovide a closure and bottle combination in which a hermetic seal andanchorage is established between the bottle and closure by mereinsertion of the closure; to provide an' improved closure for bottles bywhich internal pressures higher than atmospheric can be built upordeveloped within the bottle or like container without leakage or lossof such internal pressure through or about such closure; to provide aclosure for bottle necks having anchoring interconnections and sodisposed that no leverage exerted by a closure-penetrating needle canpry out the closure; to provide a flangeless stopper plug and bottlecombination, requiring no tear-off, which can be autoclaved withoutleakage, seepage, or disruption of the continuity of its hermeticsealing; and other objects and advantages will become more apparent asthe description proceeds.

In the accompanying drawings:

Fig. 1 represents a perspective view of the preferred embodiment of theimproved valve of this invention;

Fig. 2 represents a fragmentary vertical section through a portion of abottle with the valve insert in position engaging the internal ring inthe neck of the bottle and thus anchored to the bottle in the mouththereof prior to the evacuation of air from the bottle;

Fig. 3 represents a similar fragmentary vertical section of the sameparts after the internal evacuation of the bottle has been completed andthe atmospheric air externally effective on the valve has partiallydistorted the valve in sealing same upon the bottle, showing the changedrelationship of the anchoring groove of the valve on the fixed ring orinternal head of the bottle, by which the upper surface defining ananchoring groove of the resilient valve establishes sealing contact withand against the internal ring in the bottle neck, and the valve shankexpands radially under the pressure to tightly engage against the innerwalls of the neck of the bottle above the inner ring thereof;

Fig. 4 represents a similar fragmentary vertical section through thesame parts after the enclosing, flangeanchoring tear-off cap has beenspun thereon under axial pressure, forcing the lateral flange of thevalve tightly against the bottle end in hermetic sealed relationthereto;

Fig. 8 represents a fragmentary section through the neck end of a bottlewith a modified, unventing, form of closure plug anchored therein andeffecting a hermetic seal without either an internal vacuum or internalpressure;

Fig. 9 represents a fragmentary enlarged section of the assembly of Fig.8 illustrating the general surface relations of the bottle and closure;

Fig. 10 represents the same fragmentary assembly as Fig. 8, but with aninternal pressure produced by pumping air through a hypodermic needle,for instance, showing the expansion and enhanced hermetic sealingrelation of the closure and bottle neck end;

, Fig. 11 represents a fragmentary enlarged section of the assembly ofFig. 10;

Fig. 12 represents a bottom or reflected plan of the modified form ofclosure illustrated in Figs. 8 to 11, indieating and emphasizing theabsence of venting means therein;

Fig. 13 represents a fragmentary section of the closure web showing indotted lines the distortion occurring when a hypodermic needle is forcedthrough the convex end of the web, with enhanced sealing of the punctureupon withdrawal to hold the added or inserted pressure against leakagethrough the closure;

Figs. 14 and 15 represent respectively a vertical transverse sectionthrough and a reflected plan of a still further modified form of closureaccording to the invention,

having enhanced venting.

All of the foregoing are taken from application Serial Number 122,425,filed October 20, 1949, now abandoned, and of which this application isa continuation-in-part.

Fig. 16 represents a fragmentary section through a bottle neck andmodified form of plug in which the plug has no flange and still effectscomplete sealing even under built up pressures internally incident onthe plug, and further which has such degree of interlock and such skirtlength that any incidental cocking of an inserted hypodermic needle isunable to cause undesired withdrawal of the plug even in the presence ofinternal preponderating purposes.

Fig. 17 represents a similar section of a slightly modified form of plugin which a thin web handle is provided by which the flangeless plug canbe forcibly withdrawn L from the bottle neck.

Fig. 18 represents a plan of the organization shown in Fig. 17.

Fig. 19 represents a side elevation of the plug closure of Fig. 16.

Fig. 20 represents a fragmentary section of a still further modifiedform of plug closure having a small and thin flange overlying the end ofthe bottle. Fig. 21 represents a fragmentary section of a still furthermodified form of plug closure having both a thin flange and a web handlefor desired retraction of the plug from the bottle neck.

Fig. 22 represents a plan view of the latter.

Fig. 23 represents a side elevation of another form of plug of shorterskirt than that of Figs. 16 and 19.

Fig. 24 represents a side elevation, partially in section, of a stillfurther modified form of the plug.

Fig. 25 represents a section of the plug of Fig. 24 in anchored positionin a bottle neck shown in section.

Fig. 26 represents a similar section after autoclaving of theorganization of Fig. 25.

The bottle 10, forming the preferred but illustrative, substantiallytransparent, container for the goods to be sealed either out of or invacuuo, or under pressure, is preferably of glass and is molded as aproduction line of automatically molded relatively heavy-neckedarticles. Obviously, other materials may be used in the container, suchas plastics or the like, but glass is at present considered best forgeneral purposes.

The bottle 10 has a neck 9, delineated internally by the lower surface11, leading downwardly into and becoming the interior surface of thebottle, which starts at the edge of the internal radial bead or ring 12,formed part way down in the neck of the bottle spaced from the end 16thereof. The neck 9 is completed by an upper internal surface 15,starting at the edge of the internal head or ring 12 and extendingupwardly, generally cylindrically, to the transverse end surface 16 atthe mouth entrance of the bottle. In practice it is frequently foundthat the end surface 16 is not exactly normal to the axis of the neck ofthe bottle, but has a slight taper or flare creating in section afrustom of a cone. This has been exaggerated in the drawings to makethis structure known, although in actual practice the angle of thesurface 16 in any radial section therethrough relative to thelongitudinal axis of the bottle in departure from the trulyperpendicular or normal is usually a very few degrees. The ring or bead12, interrupting the internal surfaces 11 and 15, is an accuratelyformed peripherally continuous internal projection, the dimensions andclearance of which from the end of the bottle mouth are correlated tothe dimensions of the closure to be described. The neck ring 12 isgenerally tapering out of the surfaces 11 and 15, and preferably having,upwardly at least, a transversely curved surface merging into the necksurface 15 in a tangent thereto, to form a curved sealed surface 19,terminating toward the axis of the bottle in a relatively thin edge. Theactual shape of the inner ring or head in section axially of the bottleneck is not critical, although the upwardly curved seating surfacethereon is preferred, shaped complementally to the surface of the valveabove the anchoring groove thereof, as will be explained. The length ofsurface 15 and the internal diameter of neck ring 12 are both such as tocomport with certain dimensions of the closure to be described. Themouth end of the bottle, externally at the outer end of the neck, isprovided with a bead extension of the end surface 16, forming a lateralprojection having a downwardly presenting shoulder 29, with which ametal cap enclosure can be engaged by spinning or the like, as shown inFig. 4.

The bottle as described can be made in any size, even as small as 10 cc.and as large as desired, even of 600 cc. or more. This bottle issubstantially standard for all types of closures as later described, andis a high production molded unit, having uniformity, cheapness andadequate accurate internal bead proportions.

For operative association with the bottle as just described, a unitaryplug closure in the form of a valve button or unit is provided,differing in certain details which will be pointed out, according to thefunctional advantages sought. It will be understood that broadly thereare two primary divisions between the closure plugs. One division isdirected to the broad proposition of maintaining a seal under a vacuum.This is exemplified by Figs. 1 to 7 inclusive, of which the latter is amodification. A still further modified form thereof is illustrated byFigs. 14 and 15, which comprises the preferred form in that in additionto the establishment and maintenance of a high vacuum similar to that ofFigs. 1 to 6, it permits the rapid passage of gases past the closure, atleast in contrast to that of Figs. 1 to 6, and is therefore of value inthe art of subliming with the contents of the bottles held under vacuumduring freezing. The second division among the plugs is comprised ofordinary sealing plug-closures which are automatically held in anchoredrelation to preclude undesired retraction while establishing at leastone substantially hermetic seal regardless of the presence or absence ofdifferential pressures internally and externally of the bottle. Thissecand division is also of primary importance in maintaining a hermeticseal during the introduction of pressure into the bottle to facilitatewithdrawal of the contents, as will be explained later herein. Thedescription will first take up and deal with the vacuum type of closure.

The valve element, in all forms of the invention shown in Figs. 1 toinclusive at least, comprises a hollow lower shank 18 and an upperflange 27 having together the general outline of a T, in elevation,modified in important detail to be pointed out, and preferably comprisesa unitary hollow molded-rubber or like resilient element. The shank 18of the valve is hollow, as noted, and is of such thickness as to affordsufficient strength for the reception or assimilation of compressive andexpansive forces to be described.

The shank 18 is rendered hollow by an axial recess or bore 20, in thepreferred form, open at the lower end and closed at the upper end by atransverse web portion 22 integral and continuous with the shank. Theweb 22 will be of the desired relative thickness as to conduce towardthe desired functioning under differential pressures, as will beexplained, and will be'contoured in accordance with desired localresults. Thus, in the form of invention in which the main purpose is themaintenance of differential internal and external pressures, whetherinternal vacuum or internal pressures, and without the adaptability forrepeated penetrations by a hypoderrnic needle, the inner upper surfacedelineating the axial bore is formed of a generally flat or, andpreferably, a concave surface 21. Where repeated penetrations by aneedle are contemplated or are to be expected in the use of thecontainer, the inner upper surface delineating the end of the axial boreis formed of a convexity 23, of the order of at least a segment of asphere, as indicated in Figs. 5, 6, and 7, for instance. The axial boremay comprise the generally cylindrical bore shown in Figs. 8 to 13especially adapted to receive internal pressures to expand the shankinto enhanced interlocking engagement with the internal neck ring orbead of the bottle, as will be explained, or it may comprise theinternally laterally enlarged generally semispherical undercut surface24 merging at the internal upper end of the preferred concave surface21, and at the lower end constricting into the axial bore extensionportion 25, as indicated in the forms of the invention shown in Figs. 1to 7, relating to vacuum type closures. The surface 25 may comprise thesubstantially cylindrical surface indicated in Fig. 6, or the boreextension may be flared outwardly, as shown in Figs. 2, 3. and 4.Externally, the shank 18 comprises a straight concentric cylindricalportion 26, which merges angularly at the upper end into the laterallyextending flange 27, having the outwardly inclined or downwardly slopinglower surface 23. Toward the lower end of the shank, transversely belowthe level of the lower portion of the bulbous inner surface portion 24,the external cylindrical portion 26 curves inwardly in a sealingshoulder 30, leading tangentially into the planar substantiallyhorizontal radial sealing surface 31. The undercut surface 31 delineatesone side of a peripheral recess or groove 32. The groove may be asubstantial V in cross section, if desired, but is preferablyrectangular, and is radially defined by the short axially extendingcylindrical surface 33. The lower surface of the recess 32 is defined bythe horizontal wall 34 generally parallel with the surface 31 whichforms at and adjacent to the peripheral edge 36 thereof the hooking oranchoring surface of the valve unit. The hook edge 36 is formed by theangular intersection of the inclined generally axial guide surface ofthe valve with transverse wall 34. The lower end of the valve iscompleted by the transverse surface 37 extending radially between thelower end of the sloping guide surface 35 and the inner cylindricalsurface 25 of the valve. In the vacuum type of closure, venting means isprovided for establishing communication between the interior of thecontainer and the upper surface 31 of the anchoring recess 32. Whilethis may take any desired form, a simple structure is comprised of theaxially extending slot 40 extending through end surface 37 totermination in a line or area 41 radially coextensive with sealingsurface 31, and extending radially of the valve from communication withthe inner surface of the recess 23 through the anchoring and guideportion 35 and 36.

In the modified form of vent, illustrated, for instance, in Figs. 14 and15, the external tapering guide surface 35 is interrupted peripherallyby the plurality of venting channels 60, extending parallel to thesurface 35 and having entrances 61 at the lower end in the surface 37,and extending to exits 62 in the surface 34. In this case, the ventingis not from the interior of the valve unit, but axially from the endthereof to communication with the lower surface of the groove 32adjacent to neck ring 12, from which venting gases find their wayaxially along the cylindrical surface 26 to passage beneath the flange27. This form of venting plug closure is applicable to anyvacuum-producing and holding uses in closures, but is particularlyadapted for sublimation in which the frozen contents of the containerare exposed to external vacuum for many hours, during which the moisturetherein is evaporated through the channels 60.

In order to secure the desired cocking of the lower surface 28 relativeto the purely radial, the flange 27 is preferably slightly thicker atthe peripheral edge 42, than it is in axial alignment with the externalcylinder 26. The upper flange surface 43 is initially in a common planecontaining the upper surfec 44 of the central island or semi-detachedcentral portion formed in part by the web 22 and delineated by theannual groove or recess 45 extending normal to the surfaces 43 and 44,well down toward the shank 18. To control distortion under stress, onewall of annular groove 45 is preferably aligned with the outer surface26 of the shank.

In use, the'sterilized bottle is filled with the material to bepackaged, to the desired level, then the sterilized valve is insertedaxially into the neck. The insertion is facile because the slot 40, orchannels 60, assist the entering guide portion to be readily collapsibleupon itsellf, through reaction'between guide surface 35 and ring 12, andthe sloping guide surface steers the advancing end of the valve past theinner bead or ring 12, until the groove 32 registers generally with thebead 12, and the latter snaps into the groove and the valve and bottleassume the general relative position indicated in Fig. 2. At this point,the outermost peripheral portion of the flange 27 at least has engagedthe outermost areas of the bottle end 16, and the hook portion 36 hasengaged beneath and anchored the valve to the bead 12. The axial lengthbetween flange surface 28 and groove surface 34 is preferablypredeterminedly a little shorter than bottle surface 15 and neck ring12, so that when first inserted as in Fig. 2, flange 27 is hermeticallysealed resiliently against bottle surface 16, although, at thisjuncture, if desired, the shoulder 30 maybe .out of sealing engagementwith neck ring 12. Alternatively, the shoulder 30 may be resilientlypulled into hermetic sealing engagement 'with neck ring 12 when the plugis initially inserted to anchored connection, in addition to the sealfrom flange '27.

With the valve in the bottle neck in the position indicated in Fig. 2,the bottle is either individually, or as one of a larger group ofsimilar bottles, subjected to sharply lowered external atmosphericpressures. This permits the relatively higher pressures internally ofthe bottle to expand, and, passing through the vent 40 or channels 60,to pass under the sealing surfaces 31 and 30, and between said surfacesand the ring 12, from whence they move axially along the outside of thecylindrical portion 26, and between flange 27 and the end of'the bottle.This venting is facilitated by the loose engagement between the internalsealing portions of the valve and bottle. In other words, there is aninitial'predetermined clear- 7 ance between the surfaces and 26 in thevacuum form of closure, greater than in the pressure plug type thereof.During the evacuation of the interiors of the bottles, the valve remainsanchored in the neck, by the engagement of the enlarged hooked portionof the valve within ring 12. After the desired extremely low pressureshave been attained internally of the bottle, the previously equal orlower external pressures are more or less suddenly returned toatmospheric pressure, which, being effective on the end surface of thevalve, manifested as weight, i. e. the weight of the column of aircreating the atmosphe'ric pressure at the particular instant altitude,which is a substantially permanent measurable factor, causes pressurewhich pushes the flange of the valve against the bottle end surface 16,and, of greater importance, pushes the deformable central plug, definedby the moat or groove 45, the end web 22 and the tubular cylinder 18axially inwardly. This moves the parts from the relative positions ofFig. 2 into the relative positions of Fig. 3. At this juncture, severalimportant events have transpired, the most important of which is thatthe central semi-detached plug portion bounded by the groove 45 hasmoved inwardly and the upper central surface of the valve assumes theconcave or dished appearance of Fig. '3. The annular slot or groove 45defines the thickness of a web of reduced thickness, by which relativeflexing can occur between the central plug portion and the outer flange27, so the latter remains pressed tightly against bottle end 16. Thecentral plug therefor forces the shank 18 axially downwardly until thesurface 31 and rounded corner engage and seal against the rounded uppersurface 19 of the bead 12. Owing to the preferred internal configurationof the valve shank, the axial pressure on the shank between the upperflange and the line of sealing valve seat engagement on ring 12 causesthe valve shank 18 to expand, forcing the outer surface 26 thereoftightly against the inner surface 15 of the bottle neck. This may beaccompanied by the movement of the anchoring portion and 36 of the valveunit downwardly slightly away from the lip or bead 12, but this makes nodifierence as its anchoring function at this point is not needed. Itwill be seen in Fig. 3 that the flange 27 has been slightly flattenedout and has been forced into sealing engagement with the end surface 16of the bottle, as a secondary seal. However, in an evacuated bottle thisflange sealing is additive and while helpful,

is not essential, as under certain conditions the flange may bedispensed with while maintaining the internal seal as described, asshown, for instance, in Figs. 16 to 19 inclusive and Figs 23. However,for long shelf life of the packaged material, and for maintenance of theexisting compound sealed arrangement, and especially for use as anordinary cork or sealing plug, without necessarily evacuating the bottlefluid content, the flange is preferred. This flange conduces to thetear-off sealing arrangement shown in Fig. 4 or of any other type. Withthe sealed arrangement as completed by the evacuation, resulting in thedisclosure of Fig. 3, a compound metallic foil sealing device of anydesired sort is provided. Illustratively this comprises a permanentinner seal having the upper axial opening 51 and the lower end spun overthe shoulder 29. This mounts the removable closure cap 52, which whenreleased can be manually removed or replaced. The two enclosures justmentioned are held in anchored relation upon and about the bottle end,compressing the flange 27 against the end of the bottle by the outertear-off portion 53, also spun over the neck 29. The pressure againstflange 27 is produced by mechanical means and is additive to anyflattening due to air weight and pressure, and contracts the outerflange 27 against the bottle end surface 16. This magnifies and enhancesthe pressure on the cylinder 18 in the bottle neck and against the neckring 12. Obviously, a single layer or thickness of tear-offi can be usedwith the evacuated bottle and valve of this invention. The valve and 8bottle assembly with an aluminum or like enclosing seal forms a perfectsealed and closed bottle, even without evacuation.

In use, after filling and sealing as described, and any necessaryshipment and storage, the outer tear-ofi' is removed. The manuallyslidable cap is then removed, exposing the end web 22 of the valvethrough the cap aperture 51. Without any other disruption of the sealedend, a needle can be inserted through the web and into the contents ofthe bottle for venting the vacuum and then for withdrawing thesterilized contents. Of course, if this is not desired, the tear-01f canbe completely removed, the flange 27 can be forced up away from thebottle end and the valve manipulated sufliciently as to permit thehigher external atmospheric pressure to pass under the sealing surfaces30 and 31 over ring 12 to the venting slot 40 or channels 60, and intothe bottle, until the internal and external pressures equalize, afterwhich the valve can be removed preliminary to withdrawing part or theentire contents of the bottle from the bottle.

In certain cases the venting means is comprised of a suction needle 70,inserted through the self-sealing web 22 of the valve unit otherwisehaving no venting slot or related means, and withdrawing the entrappedair thereby. After complete evacuation, the needle is withdrawn and theaperture which it had formed in penetrating the web closes together andcompletes the sealed bottle closure of an evacuated bottle.

In the various manifestations of the invention heretofore described, theinvention has been considered from the standpoint of its being a closurefor an evacuated container. This is an important phase of the invention,but it will be seen that the provision of a closure which is anchoredwithin the bottle neck, regardless of the question of evacuation, isitself a great advance in the known art, of especial importance in thebiological, pharmaceutical and related fields. In these fields there aremany preparations which do not require vacuum packaging, but they dorequire packages having the ability to withstand internal pressureswithout leakage or seepage of material, in facilitating withdrawal ofthe supposedly sterile contents of the bottles. An illustrative buttypical use of such closure and bottle assembly is in the dispensing ofa presently important penicillin derivative. This is provided as aliquid and is bottled in the presence of sterile atmospheric air atnormal atmospheric pressures. The closure must not only be so tight asto hold air pressure within the bottle as it builds up, it must also becapable of receiving a multiplicity of needle penetrations withoutforming a path for leakage therethrough. It must also be such a sealingassembly as to prevent seepage of the material past the plug closureprior to the final bottling in order to minimize the spoilage of thecontents by contact with untreated atmosphere. The plug closureillustrated in Figs. 8 to 12 is particularly adapted to serve all ofthese functions, as, of course, if desired, is the closure illustratedin Fig. 7.

The plug and bottle assembly of the just recited figures is identicalexternally in every way, and bears the same reference characters as thepreviously described closures, except that there is no vent providedtherein, and the inner bore is generally cylindrical in the upperportion, as indicated at 20, merging at the lower portion into theoutwardly flared curved surface 63. At the upper end the bore ispreferably closed off and defined by the downwardly extending convexity64, although, if desired, the concave surface of the earlier figures maybe used.

The external diameter of the cylindrical surface 26 of the latterfigures is closer to the diameter of the neck surface 15 than in theventing types previously described, so as more easily and quickly tocontact and seal same. After the bottle has been filled to the properlevel the closure plug of Figs. 8 to 11 is inserted under axial tensionfrom above so as to cause the anchoring lip or rim 36 to engage on theunder side of the neck ring 12. At this stage the plug is held in thebottle as shown in highly exaggerated fashion in Fig. 9. However, theplug closure is predeterminedly such in length that with the anchoringrim 36 engaged against the under surface of the neck ring 12, the flange27 is pulled into resilient engagement against the end 16 of the bottleto hermetically seal the bottle. If desired, the dimensions thereof areso proportioned that when the locking rim 36 engages the neck ring 12,the sealing shoulder 30 is pulled against the upper sealing surface 19of the neck ring 12 and inner circumference 15 of the bottle. Usually indue time after the insertion of the closure plug in the filled bottle,the assembly is held together by an automatically applied and spun metalclosure element, such, illustratively, as shown in Fig. 4. This assistsin forcing the closure plug axially inward to scaling in the bottle.

In due course the physician acquires the sealed bottle and in order tofill a hypodermic needle with a predetermined measured volume of thecontents, the hypodermic, with a measured volume of air in the cylinderthereof, has the needle thereof forced through the web 22 and outthrough the convex surface of the protuberance 64, as shown in Figs. and13, with the bottle held in a vertical position with the closure at thetop. The hypodermic is then discharged and the air entrapped therein isforced under pressure into the bottle. The plunger of the hypodermic isheld in place while the bottle is inverted to a reversed verticalposition. The plunger is then retracted, or permitted to be forced inretraction, as the entrapped air under pressure in the bottle forces theliquid constituent through the needle 71 and into the cylinder followingthe plunger. The needle is then withdrawn, the aperture 72 in the plugend substantially seals itself, some of the air pressure remains in thebottle ready to be augmented or used as it may remain for the withdrawalof the next shot. Usually additional air is forced in just ahead of eachshot withdrawn.

The plug is particularly well adapted for the reception and retention ofinternal pressure, in that it expands and enhances the tightness of theseal. As the pressure is manifested at right angles to the surface uponwhich it is incident the internal flared surface 63 under pressurepushes the lower end of the shank outwardly against the bottle toenhance the anchored lock with the neck ring. Simultaneously, the shank18 expands to force the groove 32 into tight sealing engagement with theneck ring and the sealing surfaces thereof and the inner circumference15, to assist in retaining the built up pressure without permitting thepressure to blow the plug out of the bottle. It is a feature thatalthough the planar or concave upper surface of the internal bore of thevalve unit assists in concentrating the last drops of material forentrance into a hypodermic needle, the internal pressure includes acomponent axially effective on the plug to urge it to move out of thebottle neck. This is minimized by the preferred convexity shown, as,although a small volume of fluid may exist and be incapable ofwithdrawal from the ring between the cylindrical bore and the adjacentedges of the convexity, this is relatively infinitesimal, whereas thepressure on the convexity is absorbed within or close to the convexitywithout the same axial component as would exist in the planar end of theweb, and with the interesting and important forcing of the sides of theapertures 72 together to enhance the sealing of the needle apertures.The advantages of this form of the invention, as well as the obviousmodifications thereof to attain the same or generally similar resultswill be understood.

In connection with the packaging of pharmaceutical products and thelike, according to certain past practices, a plug is provided, ofgenerally cylindrical or slightly tapered shank extent, merging at itsupper end into a transverse relatively thick flange projecting radiallyof the shank and overlying the end of the bottle neck, and held id inplace by a spun over tear-01f similar to that shown in Fig. 4 herein. Itwill be understood from the previous discussion that this is at besthighly expensive, and as pointed out hereinafter has certain inevitabledisadvantageous features militating against successful use.

The previous plug organization mentioned enters a smooth generallycylindrical neck of the bottle, with as tight a frictional fit as isfeasible for facile insertion, and reliance for sealing in laid upon theclamping action of the metal tear-off forcibly engaging the resilientflange with the end of the bottle. The only actual practical seal, ifany, in this prior art organization, is between the stopper flange andthe bottle end, and the shank contributes but little sealing effects. Inany case, to prevent blowing the stopper out of the bottle under builtup pressures, the relatively thick flange and the metal tear-off areabsolute essentials, but, as will be discussed, it is not necessarily aseal, and leakage or seepage of the contents and contamination thereofcan occur, even with the flange theoretically clamped against the end ofthe bottle neck. The minimization of the sealing effects is due toseveral variable factors, some of which attach in some degree topractically every production line of molded bottles. The end of thebottle neck, against which the flange is supposed to seal, whilenominally and superficially lying in a plane normal to the axis of thebottle neck, may not lie in a true and exact plane, but, peripherallyconsidered, may comprise relative highs and lows. The outer periphery ofthe neck itself may not be truly cylindrical, but may be slightly oval.The downwardly presenting shoulder on the outer periphery of the bottleneck upon which the tear-off is to be spun may also have relative highsand lows and may not have a parallel planar relation with the supposedend plane of the bottle. Sometimes, also, the internal surface of thebottle neck may depart from the truly cylindrical toward the slightlyoval. These fluctuations in the theoretically perfect bottle varybetween bottles and are unpredictable and seem to be incidental toshrinking and warping in the production line of molded bottles.

When the molded stopper or plug of rubber or the like is inserted in theneck of the bottle and the flange is moved into contact with the end ofthe bottle neck, there may be a relative filling up of part of thebottle neck by the shank, but this may be less than that required topreclude a thin passage along the shank to and under the flange. Thisthin passage may he present at all times, or may be a latent weakness,simply waiting the application of force to develop. The tear-off isusually applied by a machine adjusted for the imposition of a givenaxial pressure on the end of the tear-off, maintained as the latter istelescoped over the bottle neck and the outer flanged end of thestopper, while the lower or terminal edge of the tear-ofl? is spun inagainst the downwardly presenting shoulder of the bottle neck. Owing tothe unpredictable disparity of heights of adjacent bottles in a series,the axial pressure from the preset pressure element of the tear-offapplying device varies between bottles. Owing to the relative highs andlows of the end surface'of the bottle, the relatively thick flange ofthe stopper is more or less compressed against the highs, depending uponthe actual pressure functional with the height of bottle for which theapparatus has been pre-set, and much less tightly compressed against thelows on the end of the bottle. The spun-on tear-off may be closer to theperiphery of the bottle neck at some places than at others. Finally, thespun-over tear-off may be more or less tight against high points on thedownwardly presenting external shoulder, depending upon the degree ofconformance of the thickness of such external portion of the bottle neckto the average for which the apparatus is set,

while being loose against the low points on such shoultight, but havethe mentioned points of comparative looseness. What is deceptive aboutthe final assembly is that superficially they all look alike and lookproperly stoppered and sealed. In every run, however, there is thepotential of an unpredictable percentage not being completely sealed,and with autoclaving this potential is increased.

In this processingwhich is understood not to attach to those goodsdesignated as biologicals, the stoppers, bottles, and contents areusually preliminarily sterilized, and the filled, plugged containershave the metal tear-offs applied. The bottles always contain an airspace between the contents and the plug closure. The packages are thenplaced in an autoclave, in which steam at approximately 250 F., and atabout 15 p. s. i., is introduced and this temperature and pressurecondition is maintained for approximately one hour. While this procedureeffects complete sterilization instantaneously, it has two adverselycomplemental potential effects. The heat affects the rubber or likematerial of the stopper, tending to cause softening and shrinkagethereof, thus tending to loosen the effective grip of the tear-off onthe flange, as well as the previously theoretically existing sealing ofthe internal surface of the neck of the bottle with the shank of theplug, and exaggerating the actual or potential paths of seepagepotentially inherent in the entire organization prior to autoclaving.The heat also develops internal pressures in the bottle of appreciablemagnitude adequate to force the stopper out of the bottle, if it werenot restrained by the tear-off, and in any case adequate to tend toforce the contents along the actual or potential paths of leakage orseepage, to establish a train of the contents between the exterior andinterior of the bottle, conducting contamination into the bottle whenexposed to normal ambient conditions.

Unfortunately, the packages which are improperly stoppered, either withor without the autoclaving, may not be discovered on inspection and theactual deficiencies of the seal may not be discovered or may not appearfor long intervals after leaving the processor. In storage, or later inuse by the physician, however, the improperly stoppered bottles developor utilize then developed paths of seepage by which contamination of thecontents occurs, which paths are those relatively shallow spaces ofinadequate and impositive contact with relative lows in the surface towhich the stopper is juxtaposed. If not already existent as an actualseepage path, the potential seepage paths are opened upon the insertionof the physicians hypodermic needle to force air into the bottlepreliminary to withdrawing a measured charge of the bottle contents.With internal pressure thus created or built up, in either the packageswhich have been autoclaved or those which have not, these seepage pathsare traversed by the bottle contents and move axially along the shankand under the flange and out of the bottle under the internal pressures,and owing to this inadequate sealing, the entrapped air pressure slowlydissipates, carrying with it part of the liquid contacts to establish atrain of contamination, so that each succeeding shot from the samebottle must be first preceded by injection of additional air and bywhich time the bottle contents have become so contaminated as to beunsafe. This is an unsatisfactory packaging organization, both from thestandpoint of impropersealing, and also from the standpoint of cost. Thecost factors involved are those of the stopper itself, with its flangeas an essential portion of the stopper, and the tear-off, which isexpensive of itself, as well as in its application to the bottle, andyet is a heretofore absolute essential for this type of packaging. Thisprior development, poor as it is, is still better than another form ofpackage once proposed for this type of product, and long sincewithdrawn, and so far as known, having no present use whatever. Thislatter device was a form of plug used in a blown tubing ampule type ofpackage in which a constriction 12 was manually formed in a piece oftubing, of essentially rounded bead construction of variable size, witha form of plug having an upwardly presenting shoulder at the end of atapered plug portion, with the tubing complementally inwardly taperedbelow the bead as the inconstant and theoretical means for limiting theinward motion of the plug and with a thin tubular extension of the plugrising above the shoulder, not for limiting the inward movement of theplug relative to a neck ring in a molded bottle, but as an inert elementserving no scaling functions until after the ampule was cracked adjacentto the bead and the end removed, after which the tubular sleeve was bentabout the jagged end of the severed ampule section to protect thephysician from being cut thereby in withdrawing the ampule contents.This latter development was so unsatisfactory and so expensive that, asunderstood, it has been completely displaced by the flanged plug andtear-off just described.

It will be understood of this organization that if any internal pressurewas developed internally adequate to expand the plug, the reactionbetween the tapered inner end and the parallel walls of the tapered tubebelow the rounded head would have an outward axial component of suchmagnitude as to force the shoulder upwardly past the bead and blow thestopper out of the tubing. It would, of course, be impossible to subjectthe discussed package to autoclaving.

The cost of the plugs or stopper of the last used, passingly currentpackage described above with the flange, is affected by two factors. Oneis the actual weight of the rubber or like material used, and with thethick flange conventionally provided, a heavy and relatively expensiveplug is involved. Another factor in the cost of the plugs is the factthat with the heavy flange on the shank of the prior art plugs, eachmold cavity is of such total diameter that the number that can be formedin a mold, and therefore the number of stoppers cured in a single heatis sharply limited, as contrasted, for instance, with the number of moldcavities and therefore the number of stoppers cured at a single heat ifthe total diameter of the individual cavity was not greater than thediameter of the plug shank without the flange, or, as shown, forinstance, in Figs. 19 and 23 herein.

As noted, this previous practice in packaging various pharmaceuticalproducts is unsatisfactory and expensive, and has only maintained overthe years because no one prior to applicant has been able tosatisfactorily solve all of the problems attaching to such packaging andto produce a package of greatly reduced cost, which may be usedsatisfactorily when desired, without any metal tear-off application, andyet will effect complete seal, retained even under appreciable internalpressures, in substantially one hundred percent of the production run ofpackaging.

Referring to Figs. l6, 17, 20, and 21, a bottle neck 9 of a bottle 10identical with those of the earlier figures is shown, having the smoothinner neck surface 11 merging upwardly into the sloping lower surface ofthe inwardly tapering neck ring 12. The sloping upper surface of theneck ring 12, through curved surface 19, merges into the smooth necksurface 15, and the latter terminates at and merges into the end surface16 of the bottle neck. The neck surfaces 11 and 15, adjacent to the neckring 12, are both substantially cylindrical and each is concentric witha common neck axis with which the inner periphery of the neck ring isalso substantially concentric. The neck surfaces 11 and 15 may besubstantially coextensive, although, as indicated, in the usual moldedformation of the neck with the neck ring 12, the internal diameter ofthe outer cylindrical surface 15 is a little greater than that of thesurface 11. Of course, surface 11, conforming to the bottle contour atsome point below the neck ring 12 flares outwardly from the generallycylindrical. In any case, the

neck ring marks the smallest diameter in the bottle neck and there is noreverse taper of surface 11 below the neck ring bringing this surfaceinwardly toward the common axis of the neck.

It has been mentioned that the flanged plugs of the earlier figures,efiecting such unique anchoring and sealing internally of the bottle.neck, does not need the flange, which may be dispensed with. It is afeature of this invention to provide for operative association with theneck portion of a bottle a described a molded stopper plug of such axiallength that no part needs to project beyond the end of the bottle, sothat the flange is eliminated, and which further efiects such sealingclosure when inserted into the described bottle neck that the metaltear-off, always previously considered an essential, with itsconcommitant expense both in material costs and the costs ofapplication, can be obviated, which is composed of smaller amounts ofrubber or other material from which it is fabricated than the prior artflanged plugs, is of smaller diameter than flanged plugs, so that thecosts of the plugs is reduced because of the greater number of plugsthat can be molded in a single heat, and finally which is of suchsealing efiiciency that not only is an initially hermetic sealestablished by mere insertion, this seal is maintained and even enhancedby the introduction of internal pressures into the bottle, so thatseepage and liquid or air leakage from the bottle is precluded, andwhereby the introduction or internal development of reasonablypreponderating internal pressures incident to normal use is inefiectiveto blow the stopper out of the bottle neck. Additionally, the simplifiedstopper plug can be used to retain an imparted vacuum in the bottles,when. this use of the plug may be desired.

Referring to Figs. 16 and 19, an illustrative form of the simplifiedflangeless plug or stopper is disclosed. This is presently preferred foruse in those situations in which the physician inserts a hypodermicneedle through the end closure web of the. plug to first insert a chargeof air, followed by reinsertion of the needle for withdrawing a chargeof the liquid in the bottle, as the longer skirt and the less acuteangle at the termination of the skirt in a shoulder at the groove to bedescribed assists in retaining the stopper in anchored relation evenunder the presence of appreciable internal pressures and an incidentalcocking and careless withdrawal of the inserted needle, in contrast tothe shorter skirt. and more acute angle of the shoulder of the modifiedform of stopper of Fig. 23. It will be understood that the descriptionwhich follows is the same for all of these figures and bear the samereference characters, except where specifically pointed out.

Referring then to Figs. 16, 19, and 23, the plug 40 is provided,comprising a hollow shank 41 having the internal bore 42 and the uppertransverse closure web 43. The plug on its exterior peripheral surfaceadjacent to the closure web is substantially cylindrical as at 44 and ofsuch diameter as to have a tight but slidable fit in the outer mostinternal cylindrical surface of the bottle neck, which merges throughthe peripherally continuous rounded shoulder 45 into the upper surface46 of the peripheral groove 47, and spaced from the outer face of theweb 43 by a predetermined axial extent such as to permit the roundedshoulder 45 to abut against and seat upon the complemental upper curvedsurface 19 of the neck ring 12 in the bottle neck with the said outersur- 7 face gene rally flush with the end 16 of the bottle neck.

Thi flush relation does not need to be exact and this surface mayactually extend a little beyond or inwardly of said end 16. The groovemay be a V formation, if desired, but it is preferred to define thegroove 47 by generally parallel spaced surfaces comprising the uppersurface 46 already mentioned, the lower planar surface 48, and,internally, by the short axially extending generally cylindrical surface51 substantially normal to the upper and lower groove surfaces 46 and48. The plug, shank below the groove is formed by the more or lessslightly tapered external skirt surface 51, in Fig. 19, and by theshorter and more acutely tapered skirt surface 51, in Fig. 23, and therelated Figures 20, 21, and 22 to be described. The tapered surface 51-or 51' meets the lower groove surface 48 in the sharply angled shoulderportion 52. While, as shown in some of the earlier figures, the diameterof the shoulder 52 may be a little less than the diameter of thecylindrical shank portion 44, in the instant form it is preferred thatthe shoulder 52 or 52 be very close to the said diameter as that of theshank at the curved shoulder 45, for a reason to be pointed out. Itwill. be understood that both the curved shoulder. 45' and the sharpshoulder 52 are peripherally continuous.

When the plug 40 is forced into a bottle containing liquidpharmaceutical or the like 'being packaged in the bottle, the taperingend- 53 engages and is deflected inwardly by the. neck ring to suchdegree that the sloping surface 48. is guided by the thin edge of theneck ring in restrained inward distortion or collapse until the shoulder52 or 52' passes beyond the thin edge of the neck ring. This may notoccur. until after the curved shoulder 45 has substantially abutted.against the curved upper surface 19 of the neck ring. Upon passage ofshoulder 52 past the. relatively sharp edge of neck ring 12, the shankportion immediately expands with the sharp shoulder 52 crowded. orforced by the resilience of the shank. against the sloping lower surfaceof the neck ring, as the plug continues to be forced axially inward,until, if not already accomplished, the curved shoulder 45 abuts theupper curved neckring surface. The axial distortion of.

the plug under axial pressure conduces toward seating.

against the curvedupper neck ring surface, while establishing the.angular shoulder in expansive intimate forced engagement against thelower surface of the. neck ring or against the neck surface 11, adjacentto the neck ring. Owing to the angularity of the shoulder, anyincidental irregularities of the internal neck surface or of the neckring are equalized by the crowding pressure of the shoulder 52 or 52'thereagainst, and mere insertion of the plug effects hermetic seal:between the plug and the in-.

ternal' surfaces of. the neck including the neck ring. It is tobeobserved. that. additionally, when anchored in position, the surfacesdefining the groove and the respective shoulders are in axial tensiontrying to pull the shoulders closer togetherfromthe position they areforced to-assume when properly anchored, because of the rela tivedisplacements thereof caused by the axial extent and proportions of theneck ring.

Owing, it is believed, to the width of the groove of the plug of Fig.19, entrapping moisture, the plug, while completely suitable-forbiological packaging and immune to adverse eifects of any kind fromelevated internal gas pressures, does not withstand autoclaving, and inmany cases, during this. recited rigorous procedure, the plug of Fig. 19has been forced out of the bottles. To correct. this feature and toprovide a plug accounting for all of the vicissitudes to which a plugmay be subjected, while effecting and maintaining complete seal Withoutleakage, seepage or forcing out during autoclaving, or when internal airpressure is effective thereon by injection through the plug, a plug asdisclosed in Figs. 24, 25, and 26 is preferred.

Referring to these figures, a plug closure is provided comprising anupper plug element or portion 61, which is predeterminedly of slightlygreater 0. D. than the I. D. of the neck surface 15 of the bottle, andof axial upper neck ring surface 19, to the end 16 of the bottle.v

This brings the end. 62 into general transverse alignment with the end16 of the bottle, in the preferred organizaa '15 tion, when the plug isinserted and fully seated on the neck ring. It may be of shorter orlonger axial extent than the length of the surface 15, if desired.

The lower surface of the groove 64 is usually a planar surface 65separated from upper planar groove surface 63 by a very slight axialsurface 59, and preferably upper surface 63 and lower surface 65 areinitially in parallelism. Owing to the slight width of the groove,which, for purely illustrative instance, may be of the order of A of theaxial length of the plug portion or element 61, the groove may be a mereslit or an inwardly convergent tapered slit, with the groove-definingsurfaces converging inwardly to mergent jointure in a substantial lineat 59. The mergence of the upper generally planar groove-definingsurface 63 with the outer peripheral generally cylindrical surface ofthe plug portion 61 is on a curve 66 in section, such as to becomplemental to the upper surface of the neck ring 12 and its fairingcurve 19 and the inner neck surface 15, so that it conformssubstantially completely to these surfaces upon forced insertion intothe bottle neck. .Owing to the slightly greater diameter of plug portion61, however, it will be seen that insertion into the bottle neck placesthe plug portion 61 under compressive strain, enhancing both the sealand the frictional engagement of the plug portion and the bottle necksurface 15. The lower end of the plug comprises a hollow shank 67 havingan internal bore 68, preferably terminating axially inwardly generallyin line with the groove 64. The hollow shank is axially tapered as inthe outer surface 70 thereof, merging upwardly into the lowergroove-defining surface 65 in a preferably acutely angled peripherallycontinuous edge or shoulder 71. It is preferred for reasons alreadydeveloped as to Fig. 19, i. e., to preclude removal of the plug byprying out leverage from improperly angled hypodermic insertion, as wellas for its enhanced frictional effects, that the skirt or shank 67 be ofappreciable length, and illustratively this length is of the order oftwice the axial length of the plug portion 61. The skirt or shankportion 67 is flexible and is subject to resilient distortion in bothsenses radially. This is facilitated by the partial division between theplug portion and shank effected by the peripheral groove 64, enablingthe flexing of the shank in either direction radially of the shankwithout disturbing the solidity of the plug portion.

In use the plug is forced axially into the bottle neck after the bottlehas been partially filled with the material to be packaged, during whichforced insertion the shank guides past the edge 60 of the neck ring 12.The axial pressure is maintained on the plug until the sharp edge 71 ofthe shank passes beyond the edge 60, and until the plug portion has beenforced into positive seating abutment on the upper surface of the shelfeffected by the neck ring. This forms a positive stop to the axialinsertion of the plug. During this motion and the initial inward andimmediately subsequent outward flexing of the shank, any moistureremaining in the groove 64 has been so substantially eliminated as to benegligible, and the groove itself has almost disappeared as the uppersurface defining same is in tight engaging contact with the uppersurface of neck ring continued axially into tight engagement againstneck surface 15, and the acute edge 71 and the surface 65 engage thesurface 11 in its mergence into the lower surface of the neck ring, withthe latter engaging the neck ring up to and possibly slightly inwardlybeyond the inner peripheral edge 60 of the neck ring.

The resilient expansion of the shank, after the forced insertion intothe bottle neck brings an appreciable portion at least of the outersurface 70 of the shank into conforming contact with the reverselytapering neck surface 11 of the bottle neck, and groove surface 65, edge71 andsurface 70 effect anchoring engagement with the surface 11 and thelower surface of the neck ring to preclude withdrawal of the plug unit.

When the plugs of Fig. 19 or Fig. 24 are inserted under axial pressureas described, until the upper groove-defining surface abuts the upperneck ring or shelf surface, and the shank expands by its own resilienceunder the neck ring and against the downwardly flaring neck surface 11,the plug is anchored securely in hermetically sealed relation andrequires no tear-off or other supplemental anchorage or covering means.The packages may be shipped and stored until use without leakage. Theexposed end of the plug may be wiped with alcohol or the like tosterilize same, a needle can then be inserted through the plug into thebottle without any fear that misplaced angles of insertion or awkwardwithdrawals may be able to force the withdrawal of the stopper. Theneedle may be used to force air into the bottle preliminary towithdrawal of a charge of the bottle contents, and this charge of airpressure can be repeated as often as is necessary or practical withoutforcing the stopper out of the bottle, even in the absence of theexpensive tear-off.

When properly fully inserted the plug has an initial anchorage of theresiliently expanded shank, in the position to which it springs backafter passing through the constriction presented by the inner peripheraledge 60 of the neck ring. This expansion of the shank toward its initialmolded position or attitude being effective against an upwardlyconvergent surface 11 has frictional and other anchorage effects as tobe adequate of itself to make it extremely difiicult to remove a plugonce it has been fully inserted and seated, even without internalpositive air pressure. When air pressure begins to build up in thebottle, through the charges of the needle or otherwise, the expansiveforces are normal to all of the surfaces of the shank of the valve, andthe small axial component thereof on the shank is inadequate to forcethe plug out, as this force is insufiicient, initially at least toovercome the anchorage effective from the mere return-expansion of theshank upon insertion, and the much larger radial or substantially radialcomponents of expansive force on the tapered bore surface are effectiveto progressively force the shank in expansion against the downwardlyflaring surface 11, to so increase the friction between these surfaces,that even a larger value of the axial component of the expansive forceis inadequate to blow the plug out of the bottle.

Moreover, due to the fact that the formation of the neck ring presentsthe surface 11 forming the inner surface of the bottle neck and thelower surface of the neck ring as a downwardly outwardly flaringsurface, the lateral or radial force on the expanded shank develops adownward axial component on the shank developing tension on the plugeffective on the upper plug portion thereof and pulling it down intoincreased and enhanced sealing engagement with the upper surface of theneck ring. This radial expansion of the shank against the reverselytapered neck surface 11 and its functioning under inserted or addedpressure, as noted, is characteristic of the plugs of Figs. 19 and 24.But the plug of Fig. 24 is additionally susceptible to autoclaving, andthen to subsequent insertion of added air pressure without causingleakage, seepage, or blow-out of the plug.

Referring to Fig. 25, the plug shown in Fig. 24 is slightly greater indiameter than the internal diameter of the neck surface 15 and wheninserted as shown the initial inward deformation of the shank isfollowed by outward resilient expansion in which the shank 67 may assumean attitude relative to the bottle neck as shown. In this the groove 64has substantially disappeared, except for a mere vestigial indentation,and the outer surface 70 conforms to a large area of the sloping necksurface 11. Owing to the effects of the reaction between the expandingshank 67 and the sloping wall surface, especially if the contactingsurfaces are initially moist,

17 the axial component developed by reaction exerts strong tension onthe plug portion 61, pulling it toward its scal ing seating on thesurfaces of the bottle neck with which it contacts.

When placed under the heat and pressure of the autoclave, the airentrapped in the bottle beneath the plug expands and develops internalpressure in the bottle. This is increased by the formation of steamtherein by the heat of the autoclave. This presents an internalcompression of considerable magnitude efiective among other areas on theinternal bore surfaces of bore 68, progressive'ly effective to forcethesurface 70 of the wall of the shank 67 to conform tighter and tighter toand against the sloping walls 11, with an actual elongation of the shanksubstantially to the position shown in Fig. 26. This is accompanied byenhanced sealing of the plug portion 61. The dimensions of plug portion61 do not change with autoclaving. As the plug is softened and driedwith a loss of some of its resilience, it is probable also that anypre-existing moisture between the neck surface 11 and the externalconforming surfaces of the shank of the plug. is driven off, with anenhancement of the frictional effects therebetween, to assist inmaintaining the plug in sealing relation in the neck. At any rate,despite the heat, and the internal pressures, the plug maintainshermetical seal, precludes seepage or leakage and does not blow out, andrequires no tear-E to complete a perfect package. After autoclaving thepackage remains one in which the physician can force air from ahypodermic through the plug and into the bottle, to elevate the internalpressures for the withdrawal of charges of the bottle contents, withoutdisruption of the permanent non-leaking, non-seeping hermetic seal, andwithout danger of blowing the stopper from the bottle.

It will be understood of any of the plugs described that although rubbermay be the preferred material, any available alternates may be used,whether they be artificial or synthetic, rubber, or a mixture thereof,or any of the polymeric materials, or the like provided a useable degreeof resilience attaches thereto.

There are many situations in which a permanent or semi-permanent closureis sought in cases where tight seal and low cost are factors, evenwithout the ability to withstand prying-out forces of a needle or thelike, as when the packaged product is not in fluid form, and such highlyefficient anchored closure effected by the slightly smaller and cheaperplug shown in Fig. 23. In some cases it is desired to providemodifications of the plugs whereby the tight seal effected may benegated by manual manipulations. This is provided as indicated in oneform of plug in Figs. 17 and 18, in which a plug, otherwise identicalwith that of Figs. 16 and 19, is provided with a small thin axiallyprojecting tab or tongue 55, by which the inserted plug can be manuallyforcibly withdrawn when desired, for reinsertion and use inreestablishing hermetic anchored engagement and seal, when desired.

In some cases where the goods are not so critical it is desired toprovide plugs with enhanced releasing possibilities. As shown in Fig'20, the plug, otherwise like that of Fig. 23, may have a thin flange 56for overlying the end of the bottle to assist in prying same out.Finally, a plug like that of Fig. 23 may be provided with a thin flange57, and also mount a tab or tongues 58 for manual withdrawal, and whenit is desired to withdraw the stopper completely for withdrawal of thecontents, as is also contemplated of the form of invention shown in Fig.17.

An important feature of the plug closures of Figs. 19, 23, and 24 isthat although both are capable of complete anchorage and retention ofseal under internal pressures, although the plug of Figs. 19 and 24 ismore immune to undesired and inadvertent dislodgement by action of aninserted needle withdrawn at an angle to the truly axial, both plugs arecapable of maintaining a complete seal under vacuum conditions, evenwithout the vent of some of the earlier figures. In using these pressureplugs for vacuum purposes, the package can beplaced in an evacuatedreceptacle,- to remove air therefrom', and the plugs forced into thebottles by appropriate means operative in said receptacle during its'evacuation. Thus, a single flangeless plug can be used interchangeablyfor vacuum or internal pressure conditions.

The high commercial value and the manifold advantages of the invention,both in the bottle, in the closure, and in the combination will also beunderstood.

Having thus described my invention, I claim:

1. A bottle and stopper combination susceptible to autoclavingpressurescomprising a bottle having an internal neck surface of predetermineddiameter, a neck ring projecting inwardly from said surface andterminating in a-peripherally continuous edge of acute angularityaxially of the bottle neck, a closure plug of resilient materialcomprising a solid plug portion of generally cylindrical form, theexternal diameter of which is not less than the internal diameter ofsaid neck,- a tapered hollow shank portion integral with the plugportion, a peripherally continuous slit-like groove partially defined bya generally planar upper surface merging by a curve into the generallycylindrical plug portion and of general conformance in profile with theupper surface of the neck ring, said groove defined in the other part bya generally planar surface merging into the shank by an acutely anglededge, said groove defining surfaces being so close together that uponinsertion of the closure into the neck the groove surfaces are stressedinto intimate contacting engagement with the respective surfaces of theneck ring with inappreciable spacing of material of the closure and theneck ring whereby the shank and plug are placed in tension stressadjacent to said neck ring to enhance the seal on both surfaces of theneck ring and liquid retention space between the neck ring and saidclosure is substantially obviated.

2. A bottle and stopper combination susceptible to autoclaving pressurescomprising a bottle having an internal neck surface .of predetermineddiameter, a neck ring projecting inwardly from said surface andterminating in a peripherally continuous edge of acute angularityaxially of the bottle neck, a closure plug of resilient materialcomprising a solid plug portion of generally cylindrical form, theexternal diameter of which is not less than the internal diameter ofsaid neck, a tapered hollow shank portion integral with the plugportion, a peripherally continuous groove notch like in sectionpartially defined by a generally planar upper surface merging by a curveinto the generally cylindrical plug portion and of general conformancein profile with the upper surface of the neck ring, said groove definedin part by a generally planar surface merging into the shank by anacutely angled edge, said groove defining surfaces being so closetogether that upon insertion of the closure into the neck the groovesurfaces are stressed into intimate contacting engagement with therespective surfaces of the neck ring with inappreciable spacing ofmaterial of the closure and the neck ring whereby the shank portion andplug portion are placed in tension stress adjacent to said neck ring toenhance the seal on both surfaces of the neck ring and liquid retentionspace between the neck ring and said closure is substantially obviated,the internal surface of the bottle neck having a downward outward flarefrom said neck ring and said shank expanding against said internalsurface under increased internal pressures to enhance its frictionalengagement beneath said neck ring and developing an axial force tendingto force said plug portion into tighter engagement against the outersurface of the neck ring.

3. In combination, a bottle having a neck formed internally with agenerally cylindrical outer surface merging inwardly into a transverseinternally tapered integral 19 neck ring the lower surface of whichtapers outwardly into a generally cylindrical inner neck surface belowthe neck ring, and a sealing plug therefor, said plug comprising anintegral closure unit of resilient material forming an upper plugportion of not smaller diameter than the said outer neck cylindricalportion and of axial extent not appreciably greater than the axialextent of said neck outer surface, said unit having a single peripheralgroove spaced from both of its ends, the said plug portion mergingaxially into said groove in a first shoulder substantially curvilinearin section and being substantially solid for its effective axial extentand relatively highly resistant to resilient deformation whereby whendisposed in said neck the plug engages laterally the outer cylindricalsurface of said neck with said first shoulder in sealing positiveabutment against the upper surface of said neck ring, said unit furthercomprising a tapered shank portion forming at its upper external end asecond shoulder merging into said groove and engaging the lower surfaceof said neck ring, said shoulders being axially spaced in the outerperiphery of the unit to define the groove as inwardly tapering andslitlike so that the respective shoulders engage the neck ring underaxial tension when fully inserted in said neck, said shank portion beinghollow and much less resistant to resilient deformation than said plugportion whereby internal pressures on said shank portion in expandingsame against the lower surface of the neck ring and the inner necksurface therebelow exerts additional tension on the plug portion pullingit down to enhance sealing by said first shoulder against said neckring, while maintaining and augmenting a seal against the lower surfaceof said neck ring.

References Cited in the file of this patent UNITED STATES PATENTS343,647 Morehouse June 15, 1886 781,182 Brewington Ian. 31, 19051,188,998 Rood June 27, 1916 2,155,811 Tredup Apr. 25, 1939 2,173,571Jesnig Sept. 19, 1939 2,215,392 Freeman Sept. 17, 1940 2,324,237 ReichelJuly 13, 1943 2,368,431 Smith Jan. 30, 1945 2,370,535 Harrison Feb, 25,1945 2,577,780 Lockhart Dec. 11, 1951 2,687,831 Miller Aug. 31, 1954FOREIGN PATENTS 9,239 Great Britain of 1903

